I. Field of the Invention
The present invention relates to fuel management systems for aircraft using turbine engines.
II. Description of the Prior Art
Turbine engines are frequently used for aircraft, especially unmanned aircraft of relatively small size. Minimizing the number and size of components for such aircraft has been a constant challenge to engineers and designers for such systems. Therefore, it has been proposed in the past to use systems which are as fully integrated as possible and which require little or no supply and control from external sources.
A particular problem in this area has been the duplication of functions and equipment for various systems of the aircraft. Such duplication increases the weight and size of aircraft components and in the case of some unmanned aircraft, the overall size of the craft. An additional problem in the past has been the inexpensive provision of a suitable engine which is capable of handling any of various fuels for propulsion.
Since unmanned aircraft and some of manned aircraft require a great range of operation, fuel efficiency has been an overall design concern. In the past, efforts have been made to determine the most efficient fuel flow rate for a given aircraft in accordance with its airframe, weight requirements, and other factors. A problem inherent with specifying such an optimum fuel flow rate is that the aircraft is not thereafter responsive to variables which affect the airframe as well as engine operating variables. Thus, all of the above problems have added to the overall cost of providing such an aircraft with the proper fuel flow control while maintaining acceptable operating standards.